Production of molded bodies from an inorganic-organic hybrid polymer with high resolution using 3D printing, molded bodies with a high flexural strength and elastic modulus, and the use thereof for dental purposes

Abstract

The invention relates to a method for producing a shaped body by means of a radiation-induced printing process according to the technique of the one-photon polymerization process, characterized in thatthe shaped body is produced by solidifying a liquid or viscous material which contains a polysiloxane component produced by hydrolytic condensation of one or more monomeric silanes having exclusively two or three hydrolyzable groups and at least one organically polymerizable radical being bonded to the silicon atom via carbon, and contains an initiator and/or catalyst for the radiation-induced polymerization of the organically polymerizable residue, andthe solidification is effected by directing light onto a region of a surface of a substrate, whereby a layer of the material located there is polymerized and thereby solidified, whereupon further layers are successively solidified.Furthermore, the invention relates to a shaped body based on an organically polymerized silica (hetero)polycondensate, which was produced by organic polymerization of the aforementioned polysiloxane component, with superior mechanical properties.

What is claimed is: 
     
       1. A method for producing a shaped body with the aid of a radiation-induced printing process according to the technique of the one-photon polymerization process, characterized in that:
 the shaped body is produced by solidifying a liquid or viscous material which contains a polysiloxane component formed by hydrolytic condensation of one or more monomeric silanes having exclusively two or three hydrolyzable groups and at least one organically polymerizable radical being bonded to the silicon atom via carbon, and an initiator and/or catalyst for the radiation-induced polymerization of the organically polymerizable radical, and 
 the solidification is effected by directing light from a radiation source onto a region of a surface of a substrate, a layer of the liquid or viscous material located there being subjected to organic polymerization by the action of radiation and thereby solidified, whereupon further layers of the liquid or viscous material, each of which is located on the layer of the last solidified material, are successively solidified with the aid of this radiation source, 
 wherein the shaped body is in the form of a composite which, in addition to the organically polymerized silica (hetero)polycondensate, contains at least one filler selected from fillers consisting of agglomerated or dispersed inorganic nanoparticles having particle sizes in the range from 5 to 100 nm and particles in the size range from 150 μm to 5 μm and combinations thereof, wherein the filler content of the shaped body is at least 15% by weight and wherein the shaped body has a flexural strength of at least 130 MPa and/or a modulus of elasticity of at least 5.0 GPa. 
 
     
     
       2. The method according to  claim 1 , wherein the liquid or viscous material is in a bath container having a bottom which is at least partially translucent, and the substrate is a platform immersed in the liquid or viscous material and movable away from the bath bottom. 
     
     
       3. The method according to  claim 1 , wherein the shaped body, after its formation in the interior of the bath, is removed from the latter, washed with a solvent, dried and is then either (a) thermally post-cured, whereby a peroxide can be added to the bath material as initiator for the thermal curing, or (b) post-cured by photoinitiation. 
     
     
       4. The method according to  claim 1 , wherein the liquid or viscous material is a composite containing a particulate or fibrous additive. 
     
     
       5. The method according to  claim 4 , wherein the refractive index of the particulate additive prior to solidification is greater than that of the polysiloxane component. 
     
     
       6. The method according to  claim 1 , in which the liquid or viscous material comprises a material which is in particle form or is dissolved in the polysiloxane component and which is capable of absorbing light of a wavelength corresponding to the wavelength of the radiation source used. 
     
     
       7. The method according to  claim 1 , wherein the polysiloxane component contains aryl groups attached to radicals bonded to silicon via carbon atoms. 
     
     
       8. The method according to  claim 1 , wherein the polysiloxane component contains phosphonic acid groups, phosphinic acid groups, phosphate groups, sulphonic acid groups, sulphinic acid groups and/or carboxylic acid groups, each of which is attached to radicals bonded to silicon via carbon atoms. 
     
     
       9. A shaped body based on an organically polymerized silica (hetero)polycondensate which has been formed by organic polymerization of a polysiloxane component which has been produced by hydrolytic condensation of one or more monomeric silanes having exclusively two or three hydrolysable groups and at least one organically polymerizable radical being bonded to the silicon atom via carbon, obtainable with the aid of a radiation-induced printing process according to the technique of the one-photon polymerization process, characterized in that:
 the shaped body is produced by solidifying a liquid or viscous material which contains a polysiloxane component formed by hydrolytic condensation of one or more monomeric silanes having exclusively two or three hydrolyzable groups and at least one organically polymerizable radical being bonded to the silicon atom via carbon, and an initiator and/or catalyst for the radiation-induced polymerization of the organically polymerizable radical, and—the solidification is effected by directing light from a radiation source onto a region of a surface of a substrate, a layer of the liquid or viscous material located there being subjected to organic polymerization by the action of radiation and thereby solidified, whereupon further layers of the liquid or viscous material, each of which is located on the layer of the last solidified material, are successively solidified with the aid of this radiation source, and 
 the shaped body has a flexural strength, as determined with a 3-point flexural test according to test standard DIN EN ISO 4049: 2009 with the universal testing machine Z100 of the company Zwick/Roell, with the changes that instead of water storage a dry storage preceded and that the feed rate was 3 mm/min, of at least 60 MPa and/or a modulus of elasticity, as determined in the linear range of the stress-strain curve between 10-20 MPa over the secant, of at least 1.4 GPa, 
 wherein the shaped body is in the form of a composite which, in addition to the organically polymerized silica (hetero)polycondensate, contains at least one filler selected from fillers consisting of agglomerated or dispersed inorganic nanoparticles having particle sizes in the range from 5 to 100 nm and particles in the size range from 150 μm to 5 μm and combinations thereof, wherein the filler content of the shaped body is at least 15% by weight and wherein the shaped body has a flexural strength of at least 130 MPa and/or a modulus of elasticity of at least 5.0 GPa. 
 
     
     
       10. The shaped body according to  claim 9 , which is built up in a spatial direction from individual layers with a thickness in the range from 10 to 150 μm or in which the layers have been formed by continuous exposure to light. 
     
     
       11. The shaped body according to  claim 9  with a flexural strength of at least 100 MPa and a modulus of elasticity of at least 3.2 GPa. 
     
     
       12. The shaped body according to  claim 9 , which contains dispersed inorganic nanoparticles with particle sizes in the range from 5 to 100 nm and particles in the size range from 150 nm to 5 μm. 
     
     
       13. The shaped body according to  claim 9 , which further comprises a material capable of absorbing light in the wavelength range from 320 nm to 480 nm.